topic Re: NATing source IP on 3745 switch in Network Security

NATing source IP on 3745 switch

GW M — Mon, 11 Mar 2019 15:05:27 GMT

I have a 3745 switch running IOS 12.3. I would like to NAT the inside IP address 192.168.1.70 to IP address 125.255.251.1 only when it is communicating to IP address 149.100.114.1. For all other IP addresses that it will be communicating with, I DO NOT want to NAT 192.168.1.70. Does anyone know what the commands are to do this?

Re: NATing source IP on 3745 switch

Jon Marshall — Mon, 16 Mar 2009 15:09:32 GMT

Do you mean 3745 router ?

If you mean 3750 switch you can't NAT on switches other than the 6500 but assuming you mean router

access-list 101 permit ip host 192.168.1.70 host 149.100.14.1

ip nat inside source static 125.255.251.1 192.168.1.70 route-map NAT

route-map NAT permit 10

match ip address 101

Jon

Re: NATing source IP on 3745 switch

GW M — Mon, 16 Mar 2009 15:16:15 GMT

It's a router

Re: NATing source IP on 3745 switch

Jon Marshall — Mon, 16 Mar 2009 15:21:10 GMT

then you should be fine.

Jon

Re: NATing source IP on 3745 switch

GW M — Mon, 16 Mar 2009 15:23:06 GMT

Thank you..

Re: NATing source IP on 3745 switch

GW M — Mon, 16 Mar 2009 15:34:29 GMT

Wouldn't "ip nat inside source static 125.255.251.1 192.168.1.70 route-map NAT" be reversed? Like... "ip nat inside source static 192.168.1.70 125.255.251.1 route-map NAT" since the source is 192.168.1.70 and we are NATing to 125.255.251.1?

Re: NATing source IP on 3745 switch

Jon Marshall — Mon, 16 Mar 2009 15:42:51 GMT

Gregg

Yes, my apologies. I was in Pix/ASA mode for a moment there where you reverse the addresses but on a router you are quite right the statement would be

ip nat inside source static 192.168.1.70 125.255.251.1 route-map NAT

Once again, apologies for that.

Jon

Re: NATing source IP on 3745 switch

GW M — Mon, 16 Mar 2009 16:50:31 GMT

no problem. Just wanted to make sure. Thanks again.